AMOS-4

AMOS-4 is an Israeli commercial communications satellite operating in geostationary orbit, catalogued under NORAD ID 39237 and international designator 2013-045A. Launched in late August 2013, the spacecraft forms part of the long-running AMOS series maintained by Spacecom Satellite Communications, a Tel Aviv-based operator with a history of deploying orbital assets to serve broadcast, broadband, and telecommunications markets across multiple continents. Built by Thales Alenia Space and massing approximately 4,250 kilograms at launch, AMOS-4 represents a substantial investment in orbital infrastructure by the Israeli commercial space sector.

Mission and Purpose

AMOS-4 was conceived as a commercial communications satellite intended to extend and complement the coverage footprint already established by earlier members of the AMOS constellation. Spacecom, which has long positioned itself as a regional and international provider of satellite capacity, operates the craft to serve customers requiring reliable relay services for broadcasting, data distribution, broadband internet access, and related telecommunications applications.

The specific mission configuration of AMOS-4 — including the precise frequency bands it operates in, the number and arrangement of transponders aboard, and the geographic coverage zones it serves — is not fully detailed in publicly available orbital catalogs. The mission type and current operational status are recorded as unknown in the authoritative tracking record, which reflects the fact that commercially sensitive technical parameters are frequently withheld by operators. What can be stated with confidence is that the satellite was placed into a geostationary slot chosen to optimize its service area, a choice that would have been driven by Spacecom's commercial agreements and the regulatory coordination processes managed through the International Telecommunication Union.

The AMOS series as a whole has served regions spanning Europe, the Middle East, and parts of Asia and Africa, and AMOS-4 was understood at the time of its deployment to extend that reach, particularly toward the Far East. However, readers should note that mission-specific details beyond what the verified catalog record provides are not confirmed here.

Orbit and Tracking

AMOS-4 occupies a geostationary orbit, the class of orbit defined by an altitude and inclination that causes a satellite to appear stationary relative to a fixed point on Earth's surface. This characteristic makes geostationary slots extraordinarily valuable for communications applications, since ground-based antennas can be pointed at a fixed position in the sky rather than tracking a moving target — a practical and economic advantage that has driven the congestion of the geostationary arc since the earliest days of commercial satellite communications.

The orbital parameters recorded in current tracking data place AMOS-4's apogee at 35,806 kilometers and its perigee at 35,784 kilometers above Earth's surface, yielding a nearly perfectly circular orbit with only 22 kilometers of variation between its highest and lowest points. This tight circularity is precisely what mission planners aim for in geostationary operations, and it is maintained over time through periodic station-keeping maneuvers using onboard propellant. The orbital inclination is recorded at 0.0 degrees, confirming the satellite sits directly above the equatorial plane — a defining characteristic of the geostationary regime. Its orbital period of 1,436.2 minutes aligns closely with the rotational period of Earth itself, which is what produces the apparent stationary position as observed from the ground.

Tracking agencies assign AMOS-4 its NORAD catalog identifier of 39237, and it is formally identified in international records under the COSPAR designator 2013-045A, indicating it was the primary payload of the 45th orbital launch of the year 2013. As of the time this record was compiled, the satellite remains in orbit and has not undergone atmospheric reentry or been recorded as decayed. Objects in true geostationary orbit are not subject to meaningful atmospheric drag at their altitude, meaning they are effectively permanent fixtures of the orbital environment unless actively deorbited or moved to a graveyard orbit above the geostationary belt at the end of their operational lives.

Because AMOS-4 is positioned in geostationary orbit at roughly 35,800 kilometers altitude, it is far too faint and distant to be observed with the naked eye under ordinary circumstances. Amateur observers with moderate to large telescopes can, in principle, detect geostationary satellites as slowly drifting points of light against the stellar background, but AMOS-4 offers no particular observing advantage over other assets in the arc and does not qualify as a readily visible object for general skywatchers.

Design and Operator

AMOS-4 was manufactured by Thales Alenia Space, the Franco-Italian aerospace prime contractor with a long track record of producing commercial communications satellites for operators around the world. Thales Alenia Space has supplied spacecraft to numerous international customers and is known for constructing platforms capable of supporting high-capacity communications payloads over long service lives. The specific satellite platform on which AMOS-4 is built, and the detailed technical specifications of its payload module, are not confirmed in the public catalog record consulted here.

At launch, AMOS-4 had a recorded mass of 4,250 kilograms. This figure is consistent with the mass class of a mid-to-large commercial geostationary communications satellite of the era, a category that typically encompasses a sizable propellant load for orbital insertion and station-keeping alongside the communications payload itself. The satellite was lifted into orbit on August 30, 2013, with launch occurring at 20:00 Eastern Daylight Time — corresponding to 00:00 UTC on August 31, 2013 — making it an evening departure from the launch site in terms of North American timekeeping.

The operator, Spacecom Satellite Communications, is an Israeli commercial entity headquartered in Tel Aviv. Spacecom has managed the AMOS constellation for a considerable period and has pursued geostationary slots that allow it to compete in regional satellite services markets. The company is registered in Israel, which is the owner country of record for AMOS-4 in international orbital catalogs. Israel has developed a notable presence in the commercial satellite sector relative to its size, with Spacecom serving as the primary commercial satellite operator representing Israeli interests in the geostationary arc.

Current Status and Significance

AMOS-4's presence in the catalog with no recorded decay date confirms that, at the time this record was assembled, the spacecraft remains an element of the active orbital population. Whether it continues to provide commercial communications services, has been placed in a reduced operational mode, or is being maintained in orbit for any other purpose is not detailed in the public tracking record. The mission status field is recorded as unknown, which is a common situation for commercial communications satellites whose operators are not required to publish operational updates to general-purpose tracking databases.

From a broader perspective, AMOS-4 is a representative example of the generation of commercial geostationary satellites launched in the early 2010s — a period characterized by high demand for orbital capacity driven by expanding broadband and broadcast markets, particularly across regions of Africa, the Middle East, and Asia where terrestrial infrastructure remained limited. Satellites of this era and mass class were typically designed for service lives of approximately fifteen years, a figure driven by the amount of station-keeping propellant they could carry and by the design lifetimes of their onboard electronics. Whether AMOS-4 is approaching or has passed such a milestone in its operational history is not recorded in the public orbital data.

The AMOS series as a whole has contributed to Israel's standing as a commercially active spacefaring nation. Operating geostationary communications satellites demands significant investment, technical expertise, and coordination with international regulatory bodies — activities that Spacecom has pursued continuously across multiple spacecraft generations. AMOS-4, as a substantial asset in that fleet, represents one node in an ongoing effort to maintain and extend Israel's commercial satellite presence in a fiercely competitive global market.

For researchers, students, and satellite enthusiasts consulting this page, the orbital parameters recorded here — particularly the near-circular geostationary orbit, the sub-degree inclination, and the close match between orbital period and Earth's rotation — offer a textbook illustration of how geostationary communications satellites are maintained in their assigned slots. The slight non-zero eccentricity visible in the apogee and perigee figures, and any future drift in inclination away from 0.0 degrees, will serve as indicators of how actively the spacecraft is being station-kept and whether it remains in routine commercial operation. Tracking records for AMOS-4 under NORAD ID 39237 will continue to be updated as new observations are incorporated into the catalog.